A normal cellular/wireless (C/W) telephone instrument is designed to operate only with a particular cellular/wireless (C/W) communication network/system and as such is designed in accord with interface requirements specific to the network/system sought to be accessed. Such requirements include modulation schemes, format, signal structure, link protocols, signal waveforms and signal frequencies. These are all unique to each network/system and a cellular/wireless telephone instrument designed to work in one cellular/wireless network/system will not function in another C/W network/system having a different operating environment.
Traveling subscribers, particularly international travelers are impacted by inoperability of cellular/wireless telephone instruments in a different C/W system, particularly in international travel. In some instances a cellular/wireless telephone instrument is designed to be operative in more than one cellular/wireless/network/system. An example is cellular/cordless telephone instruments which operate in either a cellular or cordless medium. Such a telephone instrument however carries a large overhead of redundant design and feature amenities. As a result such a telephone instrument is expensive and may even be unwieldy in size in order to support all the various features so that the user may properly interact with the different systems.
Several prior efforts have been made to accommodate the various dilemma of the traveling telephone user. A common dilemma is the different operating parameters and operating characteristics of C/W telephone instruments associated with different C/W networks. One solution to these dilemma has been to provide a “universal” telephone instrument associated with a network/system that accepts a database encoded on a card (e.g., a smartcard) to control and/or modify telephone instrument operations. This causes the telephone instrument to operate in a manner identical with operations that the user is used to in his home network/system.
Universal telephone instruments, for example, are associated with a particular network but can be programmed to mimic responses of a telephone instrument associated with a different telephone network. They often include a smartcard reader to provide a database for such purpose. The foreign user inserts a smartcard into the telephone instrument. It includes all the data as to how the telephone instrument should appear to the user, what language to use, how it should respond and how it is operated in order to make it conform to a telephone instrument that the user is accustomed to. A database of this operational information may be contained solely on the smartcard or it may be included in a database located in the universal telephone instrument. Such a technique is disclosed in U.S. Pat. No. 5,878,124, which also provides an overlay device to the telephone instrument to provide the home appearance and functions that the user is accustomed to. In this arrangement the universal telephone instrument is a specialized telephone instrument which must be provided by the system the user is attempting to access. It does not concern a cellular/wireless telephone instrument, which within the cellular/wireless network/system is personally assigned to the user and likely to be used in another system.
Personalized features of a home base network/system are provided to the traveling telephone user in using a telephone instrument in another network/system with a different exchange in which the user enters a code and a personal identification number (PIN) to any telephone instrument of a foreign system. The personalized features are retrieved from a national database, as described in U.S. Pat. No. 4,899,373, and used to provide the telephone user with his specialized features. In another aspect the features are encoded on a card which features are conveyed to the network database. Unfortunately from the point of view of a cellular/wireless telephone instrument the process does not make a C/W telephone instrument operative in a foreign network/system as opposed to providing familiar home type features to the user of a telephone instrument of a different system from the home system.
Various approaches have been proposed for making a foreign telephone user feel familiar with local telephone operations by providing features and functions such as they are accustomed to at home, but all have involved using a special “universal” telephone instrument or are limited to providing system features such as are available to a user in his home network/system. Yet to be addressed is the ability of the visitor to the system to use his own C/W telephone instrument in a new different C/W network/system. This is particularly critical in the instance of cellular/wireless, since the user prefers to use his/her own C/W telephone instrument, which he/she is accustomed to.